The present invention relates to a tube gripping apparatus for a textile machine and, more particularly, to a tube gripping apparatus for gripping a tube of the type onto which yarn is built to form a yarn package.
In U.S. Pat. No. 4,805,352 to Grassle et al., an apparatus is disclosed for exchanging full bobbins on a bobbin bank of a textile fly frame for empty bobbins. The apparatus includes a pivotable gripper assembly mounted to a traveling surface unit, a revolving peg support means having a plurality of pegs for receiving bobbins thereon and means for raising and lowering the pegs to transfer bobbins between the pegs and a creel extending overhead the traveling service unit along its direction of travel. The full bobbins on the bobbin bank of the textile fly frame are arranged in two parallel rows and are uniformly spaced from one another along each row. The creel includes two parallel banks for supporting two parallel rows of empty bobbins in reserve and the empty bobbins are uniformly spaced from one another within each creel row. The gripper assembly is operable to simultaneously transfer a plurality of full bobbins from each of the parallel rows of the bobbin bank to two parallel rows of pegs on the peg support means in the traveling service unit.
The raising and lowering means of the traveling service unit is operable to raise another pair of parallel rows of pegs toward the creel to receive a plurality of empty bobbins from each creel row and to return the thus-loaded pegs to the peg support means. Thereafter, the peg support means is revolved generally 180.degree.. The gripper assembly then grips the parallel rows of empty bobbins supported on the pegs to transfer these empty bobbins to the bobbin bank while the raising and lowering means raises the pegs with full bobbins thereon toward the creel to transfer these bobbins to the creel rows.
The gripper assembly includes a plurality of tube gripping devices each for individually gripping a tube to support the tube during the various transfer operations. In German Offenlegungschrift 37 02 279, a tube gripping device is disclosed having friction components for engaging tubes. Additionally, in German Offenlegungschrift 23 52 729, another tube gripping device is disclosed having movable clamping elements.